At present frozen together or caked granular materials in railway open cars are crushed before unloading by uniformly loosening the cargo over the full height of the open car (cf. D. I. Segal, "Loading and Unloading Equipment" (in Russian), Znamya Publishers, Moscow, 1976, pp. 26-27).
This method is, however, rather inefficient and requires large time and labour consumption. Apparatus for carrying out this method are cumbersome, complicated and exhibit high power requirements.
Known in the art in an apparatus for crushing oversized lumps of ore and rocks, comprising a casing accommodating a spring-loaded work tip (hammer) driven by hydraulic or pneumatic system. The apparatus may also be used for loosening and disintegrating caked or frozen together granular materials in railway open cars (cf. USSR Inventor's Certificate No. 340,447, Cl B02C 1/12, 1970).
Known in the art is a loosening excavator, comprising a loosening column provided with a work tip, and a vibratory mechanism comprising a double-action cylinder, vibratory impact impulses alternately acting on both the loosening column and work tip (cf. USSR Inventor's Certificate No. 371,320, Cl. E02f (5/30, 1970).
Known in the art is an apparatus for excavating hard rocks, comprising an excavating machine with a working member having teeth provided with pneumatic hammers (cf. USSR Inventor's Certificate No. 65,948, Cl. E02f 5/30, 1945).
All above-described apparatus are complicated, exhibit low efficiency and have limited field of application.
Better results are provided by a method for disintegrating a material involving application thereto of impulse shock waves induced by an explosion. Upon an explosion, a compression sawtooth wave propagates through the material. The disturbance incident on the exposed boundary of the material is reflected therefrom in the form of a tension wave. Superposition of the incident compression wave and reflected tension wave results in disintegration of the material (cf. J. S. Reinchart and J. Pearson, "Explosive Treatment of Metals" (transl. from English), Mir Publishers, Moscow, 1966, pp. 168-175).
The disadvantage of this prior art method resides in complicated realization thereof and high danger for the personnel performing the explosion operations.
Most perfect and efficient among prior art apparatus is a bulldozer for excavating frozen soil and rocks by an explosion method. The bulldozer comprises a working member mounted to a carrier vehicle. The working member incorporates combustion chambers and a exhaust pipe having its open end extending through holes provided in the working surface of the working member. The working member has work bits secured to a piston rod caused to move under the action of gases formed in the combustion chamber upon combustion of fuel mix. During the movement of the piston, the work bit connected thereto accomplishes the work to disintegrate the soil. At the same time, the gases leaving the exhaust pipes loosen the soil being treated and throw it away from the working surface of the working member thereby facilitating penetration of the working member into the soil.
This apparatus is deficient in complicated structure, high energy consumption and low efficiency when working in rocks.